Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
HO2S Monitor Code
2004 Acura 3.5RLSECTION HO2S Monitor Code
WARNING: This page is about a different car, the 2003 Acura RSX. However, it is still accessible from the selected car via links, so may be relevant.
- Do not turn ignition switch off.
- When negative battery cable is disconnected, all readiness codes are cleared.
Ensure ambient temperature is 20-95°F (-7-35°C).
- Connect scan tool to DLC.
- Start engine and hold at 3000 RPM with no load (in park or neutral) until radiator fan comes on.
- Let engine idle for 5 seconds.
- Drive vehicle at steady speed between 50 and 62 MPH for about two minutes
- With A/T in "D" position, M/T in 5th gear, decelerate from 62 MPH by completely releasing throttle for 5 seconds. If engine is stopped during this procedure, repeat step 4) and 5).
- Check for readiness code with scan tool.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.